Positive electrode material for lithium secondary battery, lithium secondary battery, and secondary battery module using lithium secondary battery

Abstract

A lithium secondary battery of excellent high temperature cycle characteristic using, as a positive electrode material, a surface-covering lithium manganese composite oxide capable of stably suppressing the leaching of Mn even at high temperature and high voltage without lowering the electric conductivity, in which the positive electrode material for the lithium secondary battery is a lithium transition metal composite oxide having a hexagonal layered structure and represented by a compositional formula: LiMnxM1-xO2 (in which 0.3≦x≦0.6, M is one or more elements selected from the group consisting of Li, B, Mg, Al, Co, and Ni), or a lithium transition metal composite oxide having a cubic spinel structure and represented by a compositional formula: LiMnyN1-yO4 (in which 1.5≦y≦1.9, N is one or more elements selected from the group consisting of Li, Mg, Al, and Ni), and the lithium transition metal composite oxide has a metal fluoride and a lithium phosphate compound on the surface thereof.

Dependencies are inferred from the claim text.